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Single Family ResidenceResidential
$464,973$447 / ft²
TopHap EstimateOur estimate of what this home would sell for today, based on nearby sales, the home's size and features, and local price trends. It is a starting point, not an appraisal.· confidence 94How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026
Last sold for $75,000 on Nov 5, 1986

509 CRABB AVE

ROCKVILLE, MD 20850
1
Baths
1,040 ft²
Living AreaTotal finished area of the structures, from county records. Some counties include shared space like hallways or a building gym, so it may not match a listing.
0.13 ac
Lot SizeThe size of the land the home sits on, from county records.
1952
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.

Valuation

$465K
$437K low$493K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$75,000 · Nov 5, 1986
Est. Owner EquityRoughly how much of the home's value the owner would keep after paying off known loans. It is our estimate minus the loans still owed.$287,973
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$230,378
Loan-to-ValueHow much is still owed on the home compared to what it is worth. 80% means loans equal 80% of our estimate, so it shifts when the estimate does.40%
1st MortgageA loan still believed to be open on this home, in the order lenders get repaid. The first position is paid back before the second.$152,000
NATIONAL CITY MORTGAGE CO · R · recorded Jun 8, 2004
2nd MortgageA loan still believed to be open on this home, in the order lenders get repaid. The first position is paid back before the second.$25,000
NATIONAL CITY BANK

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$4,859 (2025)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$386,100 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$251,700
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$134,400
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$356,200
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$386,100

Climate Risk

Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.11 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.30%
FEMA Flood ZoneFEMA's flood zone for this address. Zones starting with A or V are high risk, and lenders usually require flood insurance there.minimal

Scores 0–100; higher = greater projected risk.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
StyleThe architectural style of the home, such as ranch or colonial.Conventional
CountyMONTGOMERY
Lot (acres)The size of the land the home sits on, from county records.0.13
ConstructionThe main material the home's frame and walls are built from.Frame (Unspecified)
RoofThe main material covering the roof, such as asphalt shingle or tile.Composition Shingle
HeatingThe type of heating system in the home.Yes
CoolingThe type of cooling or air conditioning in the home.Central
PoolWhether the property has a pool, and what kind, such as in-ground.No
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 112 ft²

Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.

E
Maryvale Elementary SchoolB-
Elementary · Grades PK–5 · 0.3 mi
H
Rockville High SchoolB-
High · Grades 9–12 · 1.2 mi
M
Earle B. Wood Middle SchoolB-
Middle · Grades 6–8 · 1.9 mi

District: Montgomery County Public Schools

Neighborhood · ZIP 20850These are comparison scores, not percentages. 100 equals the national average, so 150 means about 50% above average.

CrimeLocal crime compared with the rest of the country, where 100 is average. It reflects things like population density, income, and how crime gets reported.104
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.89
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.40

Index scale: 100 = US average (tick). Lower is better.

Homes occupiedThe share of homes here that someone lives in. The rest sit empty, including vacation and for-sale homes.95%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.28%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.8%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.8%
PopulationHow many people live in this area.51,693
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,703 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$126,425
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$154,183
Average tempThe average temperature here across a full year.54°F
Annual precipHow much rain and melted snow falls here in a typical year.43 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.57%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Owner occupied
Company ownedWhether the owner is a company or trust rather than a person.No

Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.

How this home compares

509 Crabb Ave measured against every home in its neighborhood, its ZIP code and its county, using county assessor records refreshed nightly. A home can stand out in one of those areas and look ordinary in another, because each one holds a different mix of homes.

  • Worth less than 81% of homes in Rockville
  • Costs more per square foot than 88% of homes in Rockville
  • Smaller than 92% of homes in Rockville 20850
  • Older than 93% of homes in Rockville 20850

What homes are worth in Rockville 20850

Each bar is how many homes fall in that price range. The marker is this home.

This home
$186K$1.7M

This home is worth more than 19% of homes in Rockville 20850.

How it measures up in Rockville 20850

The dot is this home. The mark in the middle is the typical home in Rockville 20850.

Estimated value$464,973
CheaperTypical $751,645Pricier

Pricier than 19% of homes nearby

Price per ft²$447
CheaperTypical $339Pricier

Pricier than 88% of homes nearby

Living area1,040 ft²
SmallerTypical 2,040 ft²Bigger

Bigger than 8% of homes nearby

Lot size0.13 ac
SmallerTypical 4,138 ft²Bigger

Bigger than 55% of homes nearby

Year built1952
OlderTypical 1991Newer

Newer than 7% of homes nearby

How 509 Crabb Ave ranks against every home in each area.
MeasureThis homeRockvilleRockville 20850Montgomery County
Estimated valuepricier than$464,97319% of homes19% of homes27% of homes
Price per ft²pricier than$44788% of homes88% of homes88% of homes
Living areabigger than1,040 ft²9% of homes8% of homes9% of homes
Lot sizebigger than0.13 ac41% of homes55% of homes41% of homes
Year builtnewer than195212% of homes7% of homes14% of homes

About 509 Crabb Ave

How much is 509 Crabb Ave, Rockville, MD worth?

The TopHap Estimate for 509 Crabb Ave, Rockville, MD is $464,973 as of Jul 14, 2026. The likely range is $437,112 to $492,834. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 509 Crabb Ave, Rockville, MD last sell?

509 Crabb Ave, Rockville, MD last sold on Nov 5, 1986 for $75,000, according to the county's recorded deed.

How big is 509 Crabb Ave, Rockville, MD?

509 Crabb Ave, Rockville, MD has 1 bathrooms, 1,040 square feet of living space and a 0.13-acre lot.

When was 509 Crabb Ave, Rockville, MD built?

509 Crabb Ave, Rockville, MD was built in 1952, making it 74 years old. It is a conventional home. The building has 1 story.

What schools serve 509 Crabb Ave, Rockville, MD?

509 Crabb Ave, Rockville, MD is assigned to Maryvale Elementary School (elementary), rated B-; Rockville High School (high), rated B-; Earle B. Wood Middle School (middle), rated B-. All sit in Montgomery County Public Schools. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 509 Crabb Ave, Rockville, MD compare to other homes in Rockville 20850?

Among the 14,094 homes in Rockville 20850, it is worth more than 19% of them ($464,973 against a typical $751,645), its price per square foot is higher than 88% of them ($447 against a typical $339), it is bigger than 8% of them (1,040 ft² against a typical 2,040 ft²), its lot is bigger than 55% of them (0.13 ac against a typical 4,138 ft²) and it is newer than 7% of them (1952 against a typical 1991). Measured against all of Montgomery County, it is worth more than 27% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 509 Crabb Ave, Rockville, MD?

The 2025 property tax bill for 509 Crabb Ave, Rockville, MD was $4,859. The county assessed it at $386,100.

Closest homes

More homes in Rockville 20850

Assigned schools

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